The present invention relates to a column for distillation of charge products which have a tendency to form two-phases in a sump of the column.
Particularly, it relates to such a column for distillation of charge products having the above tendency, which is heated by a sump circulating boiler.
Columns of the above-mentioned general type are known in the art. During operation of such columns which are heated by a sump circulating boiler, as a rule difficulties occur when the charge product to be distilled has tendency to two-phase formation in the sump of the column. The heavy phase produced in this case can bring to stoppage the circulation of liquid between the column sump and the boiler required for the column heating, or at least considerably affect the same.
For eliminating these difficulties it has been proposed to provide a forced circulation between the column sump and a separate separating container by means of a pump. Thereby the heavy phase in the separating container is separated by gravity force separation, and only a light phase is pumped back into the column sump. The separating layer between the light and heavy phases is maintained constant by a separating layer regulator. This method is not free of disadvantages, since the installation of a pump for the forced circulation as well as a separate separating container cause additional installation and operational costs. Moreover, the use of the pump leads to the fact that the liquid is mixed by the pump before the entrance in the separator. The heavy phase is therefore produced only in the form of very small droplets, which naturally affect its subsequent separation.